Abstract: A method is disclosed for controlling the direction and transport of a material on a microfluidic device formed from an acrylic polymer, by electrokinetic flow of a fluid containing the material. The method comprises providing an electrokinesis buffer containing a charged hydrophilic polymer, wherein charges on the polymer are randomly distributed. The method has applications for improved transport of proteins and transport of materials comprising differentially charged chemical species. A preferred embodiment of the present invention comprises use of the disclosed method for electrokinetic separations of a mixture of polypeptides having both positive and negative charges. Another preferred embodiment concerns use of the disclosed method for performing an assay involving mixing of two or more reagents, wherein a first reagent comprises an enzyme and a second reagent comprises species having an opposite charge to the enzyme.

Abstract: The present invention concerns devices, apparatus and methods for transferring liquids. One aspect of the present invention is a device comprising a plate having a plurality of transfer elements. Each of the transfer elements comprises an aperture in the plate where the aperture is capable of being electrically activated. The plate has one of more attaching elements for attaching the plate to a multiwell plate to form a sealed system except for the apertures of the transfer elements. Usually, the device is adapted for sealing attachment to a multiwell plate. In a method in accordance with the present invention a quantity of liquid is disposed to a second side of a plate having a plurality of apertures in the plate. The apertures are capable of being electrically activated. The liquid is present in a closed well except for the apertures in the plate. To simultaneously expel liquid from the apertures, the apertures are electrically activated.

Abstract: Methods are provided for the fabrication of polymeric microchannel structures having enclosed microchannels of capillary dimension. The microchannel structures are constructed of a base plate and a cover, sealed together. Microchannel structures having walls of a plastic material are formed in a generally planar surface of at least the base plate. The cover has at least one generally planar surface, and the microchannel structures are enclosed by bonding the planar surfaces of the cover and the base plate together. In some embodiments the surfaces of the cover and base plate are both of plastic material, and are directly thermally bonded. In some embodiments a bonding material is applied to one of the surface prior to bringing the surfaces together. Suitable bonding materials are disclosed.

Abstract: The present invention concerns methods for masking inhomogeneity of a member of a specific binding pair (sbp) employed in a capillary electroseparation. The method comprises binding the sbp member to synthetic particles that become localized during capillary electroseparation. Also disclosed is one embodiment of the present invention, which is a method for conducting a capillary electroseparation specific binding assay. The method involves the electroseparation of a labeled first member of a specific binding pair that is bound in a complex from labeled first member that is not bound in the complex. The complex comprises the first member and a second member of a specific binding pair. A combination is provided comprising a sample suspected of containing an analyte, a labeled first member of a specific binding pair, and a second member of a specific binding pair under conditions for forming a complex between labeled first member and the second member.

Abstract: The present invention concerns an apparatus for conducting a microfluidic process. The apparatus comprises integral first and second plates. The first plate comprises an array of sample receiving elements for receiving a plurality of samples from an array of sample containers and dispensing the samples. The second plate comprises a planar array of microfluidic networks of cavity structures and channels for conducting a microfluidic process. Also disclosed is a method for processing an array of samples. At least a portion of each sample in an array of sample wells is simultaneously transferred to a corresponding array of microfluidic networks of cavity structures and channels by means of a corresponding array of sample receiving elements that is in integral fluid communication with the array of microfluidic networks. The samples are then processed.

Abstract: Devices and methods are disclosed for moving charged molecules through a medium by the application of a plurality of electrical fields of sufficient strength and applied for sufficient amounts of time so as to move the charged molecules through the medium. The devices although preferably small in size, preferably generate large numbers (100 or more) of electrical fields to a movement area which preferably contains a liquid buffered or gel medium. Mixtures of charged molecules are pulled through the gel by the force of the electrical fields. The fields are preferably activated simultaneously or sequentially one after another at various speeds to create complex force field distributions or moving field waves along the separation medium. Charged molecules capable of moving quickly through the gel will be moved along by the faster moving field waves and be separated from slower moving molecules.

Abstract: Integrated microfluidic devices comprising at least an enrichment channel and a main electrophoretic flowpath are provided. In the subject integrated devices, the enrichment channel and the main electrophoretic flowpath are positioned so that waste fluid flows away from said main electrophoretic flowpath through a discharge outlet. The subject devices find use in a variety of electrophoretic applications, including clinical assays, high throughput screening for genomics and pharmaceutical applications, point-or-care in vitro diagnostics, molecular genetic analysis and nucleic acid diagnostics, cell separations, and bioresearch generally.

Abstract: Electrophoretic chambers having at least a region of surface modification, and methods for their fabrication, are provided. In some embodiments the subject chambers include in the region of surface modification an anchoring polymeric layer interpenetrating the surface of the chamber and an electrophoretic polymeric layer copolymerized with the anchoring polymeric layer. The subject chambers are prepared by sequentially contacting the chamber surface with a first monomer capable of interpenetrating the surface and a second monomer capable of copolymerization with the first monomer, followed by copolymerization of the first and second monomers. In other embodiments an electrophoretic polymeric layer is noncovalently bound on the surface of a rigid polymereic base material without the aid of a separate anchoring polymeric layer. The subject devices find use in any of a variety of electrophoretic applications in which entities are moved through a medium under the influence of an applied electric field.

Abstract: Microchannels having at least an acrylic inner surface and methods of their use in electrophoretic applications are provided. The subject microchannels may be in the form of a variety of configurations suitable for holding an electrophoretic medium. The subject microchannels give rise to substantially reduced EOF and/or adsorption as compared to fused silica under conditions of electrophoresis and find use in a variety of electrophoretic applications in which charged entities are moved through a medium under the influence of the an applied electric field.

Abstract: Integrated microfluidic devices comprising at least an enrichment channel and a main electrophoretic flowpath are provided. In the subject integrated devices, the enrichment channel and the main electrophoretic flowpath are positioned so that waste fluid flows away from said main electrophoretic flowpath through a discharge outlet. The subject devices find use in a variety of electrophoretic applications, including clinical assays, high throughput screening for genomics and pharmaceutical applications, point-or-care in vitro diagnostics, molecular genetic analysis and nucleic acid diagnostics, cell separations, and bioresearch generally.

Abstract: Thermoreversible hydrogels comprising non-ionic, uncrosslinked copolymers, and methods of their use in electrophoresis, are provided. The subject copolymers comprise polyacrylamide backbones, where a portion of the acrylamide monomeric units comprise hydrogen bonding groups as N-substituents. Combination of the subject copolymers with an aqueous phase provides thermoreversible hydrogels which find use as separation media in electrophoretic applications.

Abstract: Microchannels having at least an acrylic inner surface and methods of their use in electrophoretic applications are provided. The subject microchannels may be in the form of a variety of configurations suitable for holding an electrophoretic medium. The subject microchannels give rise to substantially reduced EOF and/or adsorption as compared to fused silica under conditions of electrophoresis and find use in a variety of electrophoretic applications in which charged entities are moved through a medium under the influence of the an applied electric field.